From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: [PATCH 2/3] Add EVPD page 0x83 to sysfs Date: Fri, 07 Mar 2014 12:18:10 +0100 Message-ID: <5319AAF2.7040305@interlog.com> References: <1392286032-85036-1-git-send-email-hare@suse.de> <1392286032-85036-3-git-send-email-hare@suse.de> <20140228170131.GA31510@infradead.org> <5316D459.6070107@suse.de> <20140305194255.GA5607@infradead.org> <53183951.7080805@suse.de> <1394188779.5225.40.camel@dabdike> <5319A494.6020308@suse.de> <1394190098.14365.7.camel@dabdike> Reply-To: dgilbert@interlog.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.infotech.no ([82.134.31.41]:51783 "EHLO smtp.infotech.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751812AbaCGLS2 (ORCPT ); Fri, 7 Mar 2014 06:18:28 -0500 In-Reply-To: <1394190098.14365.7.camel@dabdike> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley , "hare@suse.de" Cc: "linux-scsi@vger.kernel.org" , "hch@infradead.org" , "jlinton@tributary.com" , "kay@vrfy.org" , "kai.makisara@kolumbus.fi" On 14-03-07 12:01 PM, James Bottomley wrote: > On Fri, 2014-03-07 at 11:51 +0100, Hannes Reinecke wrote: >> On 03/07/2014 11:39 AM, James Bottomley wrote: >>> On Thu, 2014-03-06 at 10:01 +0100, Hannes Reinecke wrote: >>>> So the only 'proper' solution would be to add a bitmap of supported >>>> pages; however, this would be 256 bits = 32 bytes of additional >>>> space required for struct sdev. >>>> Which I'm a bit reluctant do to, as it'll be a sparse array in most >>>> cases, adding to quite some wasted space. >>> >>> Why per sdev? Isn't it per target? The supported EVPD page list >>> shouldn't really vary for luns of the same target unless something very >>> strange is happening in the array. >>> >> Spec says it's per LUN: > > Specs say a lot of "interesting" things. The question is what's common > practise in the field. I have a SAS controller (not from a major) that in jbod mode sends through different physical SAS and SATA disks as different LUNs in the _same_ target. Needless to say on a target from that controller there is not a lot of commonality between its LUN's VPD page sets. Would it be possible in a sysfs VPD info directory to have a timestamp (e.g. CLOCK_MONOTONIC) of when the VPD info was read? Doug Gilbert